Just finished my install, did a reboot, and it did not work out too well. Using a Dell Inspiron 3712 laptop with UEFI. I used grub2 as a bootloader. My /dev/sda2 is my /boot partition, /dev/sda4 is my root. Boot partition is set as a fat32 file system and my root is ext4 (which i assumed correct since the handbook says vfat is a necessity for UEFI). I see grub and kernel and everything in /boot. Where do I start with trying to find the problem? By the way, in order for me to run the live disk off my USB drive I do use legacy boot mode in order to get into it (without using legacy I can't boot off usb). I have tried with and without the legacy boot option when trying to boot into my fresh install but I'm not getting anything.. Where do I start?

By the way, in order for me to run the live disk off my USB drive I do use legacy boot mode in order to get into it (without using legacy I can't boot off usb)

In order to do the necessary work in the UEFI firmware you must be booted in a UEFI operating system.
You need to make a UEFI capable live_usb. Recommend using system rescue cd. visit http://www.system-rescue-cd.org/ and download it then create the live usb per http://www.system-rescue-cd.org/Installing-SystemRescueCd-on-a-USB-stick/ . Insert the live_usb. Enter your UEFI (sometimes misidentified as BIOS on UEFI machines), ensure secure boot is disabled and UEFI mode (or UEFI and legacy mode) is enabled. Select the live_usb as first to boot. Exit the UEFI and reboot. Follow the handbook to mount the gentoo partitions and enter the chroot. Run emerge efibootmgr grub. Follow https://wiki.gentoo.org/wiki/GRUB2#UEFI_with_GPT to reinstall and configure grub._________________Defund the FCC.

a) Create a USB pendrive with Sysrescuecd and boot into it with EFI
b) Check if your partition table is GPT and the first partition is flagged as boot
c) Check if efibootmgr shows the correct boot order

I have made the experience, if the NVRAM of UEFI is not corrupted, you should always have the possibility to boot via fallback "/EFI/BOOT/BOOTX64.EFI". That means, you could copy "/GENTOO/grub64.efi" to /EFI/BOOT/BOOTX64.EFI" and restart the system should boot.
I also have to mention that I have a HP 8200 which has corrupted NVRAM. Here was the only possibility is to use a USB pendrive with Grub in "/EFI/BOOT/BOOTX64.EFI" to point to the Kernel on the harddisk.

Boot partition is set as a fat32 file system and my root is ext4 (which i assumed correct since the handbook says vfat is a necessity for UEFI).

If I'm not mistaken, only the GRUB partition needs to have vfat, not the boot partition (since it's not seen by UEFI), but I could be wrong since I don't use GRUB. Could you show us your lsblk -f so we can make sure you didn't just put the wrong partition in vfat?_________________Lord Silicon Schway
Yet another computer cultist